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Crystal Structure, Raman Spectra and Dielectric Properties of Ca0.66Ti0.66La0.34Al0.34O3 Microwave Ceramics with Nd3+Additions
Y. Xu, R. Fu, Y. Yang, J. Cai, X. Gu, J. Fang
College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 210016, Nanjing, Jiangsu
received January 3, 2016, received in revised form February 22, 2016, accepted April 13, 2016
Vol. 7, No. 3, Pages 257-262 DOI: 10.4416/JCST2016-00001
Abstract
Ca0.66Ti0.66La0.34Al0.34O3 (CTLA) ceramics doped with Nd2O3 were prepared by means of the conventional solid-state reaction method. The Nd2O3 dopant was added in the range of 0.5 – 3.5 wt%. The dielectric properties, crystal structure and Raman spectra of the CTLA ceramics doped with Nd2O3 were investigated with the Hakki and Coleman's dielectric resonant, XRD and Raman spectroscopy method, respectively. It was found that Nd2O3 promotes the densification and enlarges the crystal cell volume of CTLA ceramics. Two chemical reaction defects emerge in CTLA ceramics with the substitution of Nd3+. Nd3+ is substituted for La/Ca atoms at the A-sites of the CTLA ceramics' structure with increasing Nd2O3 doping, and the polarization of the TiO6 octahedra reaches the maximum volume when the amount of Nd2O3 doping is 2.0 wt%. Excellent microwave dielectric properties of Q×f= 37454 GHz (@4 GHz), εr = 45 and τf = 0.13 ppm/°C were obtained for CTLA ceramics with the addition of 2.0 wt% Nd2O3.
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Keywords
Ca0.66Ti0.66La0.34Al0.34O3, microwave dielectric properties, structure, additives
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